Electric circuit interrupter



Filed Nov. 10, 1948 lmver'wtoP: v Thellwell R. Coggesha,

big

His Attorneg.

Patented Oct. 9, 1951 STATES PATENT OF F ICE..

2,570,76a ELECTRICVCIRCUIT INTERRUPTER Thellwell R. Coggeshall, Bala signor' to GeneraliElectric Company, a corporaf an of New .Y

Application November 10, 1948, Serial No. 59,1296, z olaifms (c1. 200,-,.150)

This invention` relates td high` voltage lelectric apparatus in whichnseisl made of longhollowl ceramic or rother brittle insulators vand more plic'ation;` thereis disclosed acircuit interrupter contact structure is mounted within wherein the arfliousing structurecomprising an innertubular insulatingmember surrounded by outer tubular members constructed'ofy relatively heavy and brittlewceramic material. In th e 1=rinc e patent the 'innejr insulating` tubular, member' is rigidl7 ateither t end to the length ef, Snell-section which een be sup- D L'gltd` by.y a cantilever orderjto `make pdssiblean increase inthe voltage rating, of 'ajcircuit offser'ially-arranged interrupting contacts. "Onebject of my invention is toprovid'e, an

improved construction for supporting relatively, cori.Centricallyv about an 'inner insulating casingfsofasf'to lI'nalge ratin'go'tliign long and "heavy insulating shells possible an increase" in the voltage voltage electrical apparatus.

Another object of'm'y invention is the provision of 'an improved "construction for' supporting a substantially horizontally disposed outer ceramic shell of a circ'it interrupter in a flexible fashion Seniat destructive weekenden; the operation of the contacts: within rthe casing, as,l

wellas external shocksdue to ground tremors', frsrflitted. 't9 .the date" for" example, are not relativelyvr brittle` shell.

tubular insulating ,housingA a supporting chamberl and the outer ceramic l arrangement. Thus, in

interrupter v.such as. that` d i s f the Prince patient, itfis vital to .provide Still another object ofmyinvention is l,toprof/x vide. anL improvedv circuit breakerv c uistructkl whereinr the weight of an outer protective@rel ax-VM shell is taken by exible an inner insulating nontivelyrheavy vinsulating meansdisposed between brittle tubularcasing and the brittle fshell so .as tol insulate the shell from radialor longitudinal .shocks and whereinmeansareprovided forrei-` taining oil o r other. suitabler insulatingliquid within Vthe space between the innercasingandl outer insulating shell.

For protecting the outer shell from. radial shocks due vto.theoperation ,of lthe contacts with'l:y

in the inner tubular meinber,. a.J plurality offre;

. silient or flexible annular spacersare disposed at intervals longitudinally along the exteriorsur;v

face oi the inner tubular casing for supper-tm the outer shell.

sections.l liquid within the space between'thelconcentri cally disposed insulating casing and the. outer ceramic shell, adjacent. endsfof ingmeans. Furthermore, means are provided fer permitting the rvdistribution of liquid-lopende] d in'ally along the space between the inner tubular .f members, dispsed.

casing andthey outer shell thereon.

My'` invention will be better..understood.withV reference to the drawings in which Fig.. 1 is af side view partly in section of a circuitinterrupten embodyingmy invention and kin whichFig'. 2-is` an enlarged sectionalview of a interrupt'er shown .in Fig. 1.

WhileI have illustrated my inventioninkcon-,g

necton with,4 a circuit interrupter wherein l'a plurality of pairs of serially arrangedY contacts aresimultaneously operated by a common, actuatg ing member, andwherein a piston applicable to other voltage electrical apparatus as we .i

In Fig. 1 the horizontal V in terrupter unit. is ,sup-y. a ported by suitable insulating Vertical cc' l u1fr'1ns' l l rand 2. The insulating contains certain portionsofthe,contactpera ing mechanism which, f'or simplicity'. have been omitted from the drawingasthese formno part Disposed on the supportingf .column I is thelinkage mechanism housing of my invention.

c gf For protecting the. shell againstLI longitudinal shocks, annular resilient 4spacers',are disposed betweenl the adjacent endslof 'thefshell For the purpose, of retaining'insulatingn the shell secf:v tions `are suitably interconnectedrby exible seal-l`v lis i utilized force a blast of liquidbetween each pair of. contacts during the circuit interrupting opera: tion,v it will vbe''understood that `my inventionfis not limited to such an interrupter and lthat itis types Vof comparable high,

Vblast across the space erally indicated at 3, and the terminal cap generally indicated at 4 is mounted at the opposite end on the insulating supporting column 2. The structure housing the contacts is generally indicated by the numeral 5 and is supported at either end by the housing 3 and the terminal cap 4.

While the particular construction of the contacts and the operating mechanism therefor forms no part of the present invention, va brief description thereof is here included for completeness. The movable contacts 6, 1, 8, 9, and I0 are mounted upon and movable with the common connecting rod II and cooperate respectively wth the xed contacts I2, I3, I4, I5, and I6 all of which are shown by dotted lines in Fig. 1. It will be understood, of course, that suitable connecting means would be provided for insulating movable contacts 6 and I0 from each other and also a connecting strap would be used to afford an electric connection between each movable contact such as 6 and an adjacent Xed contact such as I3 such as is shown clearly in the above Prince patent, for example. Connecting rod II and operating rod II are suitably interconnected by a linkage mechanism generally indicated by the numeral I8 so that vertical movement of rod Il causes horizontal movement of rod II. The contacts 6 through ID are moved to the open position by causing the operating rod I'I to move upwardly as by releasing a latch mechanism, not shown, so as to permit suitable contact opening/springs, also not shown, to move the rod I'I upwardly.

For the purpose of causing the high dielectric arc extinguishing liquid, which occupies the space within the interrupter to the level indicated, to between the interrupting contacts, a piston means generally indicated at I9 is provided. As is disclosed in the above Prince patent, piston I9 is operable in response to operation of operating rod I'I to cause a blast of arc extinguishing liquid to circulate from the enclosing housing 3 into the interrupting unit 5 in the direction indicated by the arrows through the gate valve 2), between the interrupting contacts, and back into the housing 3. As disclosed in the above Prince patent, a baiile board containing expulsion ports adjacent each pair of interrupting contacts could be utilized to facilitate the arc extinguishing blast action of the fluid. I

The piston I9 would be arranged with suitable check valves which would allow the uid to flow from above the piston I9 to the space below the piston to permit circulation of the oil in the direction shown by the arrows and thereby to cause fresh oil to be available in the region of the contacts for each successive interrupting operation.

As may be observed from Fig. 1, the interrupting structure 5 comprises an inner tubular insulating casing 2| about which a plurality of ceramic insulating shells 22 are mounted. The insulating tube 2 I is secured t0 the housing structure 3 by means of a metallic flange member 23 which is bolted to a wall of the structure 3 by the bolts 24. As is shown in Fig. 1 the outer periphery of tubular insulating casing 2l is provided at its ends with an annular groove which cooperates with the wedge-like inner periphery of the split ring-like member 23. The right-hand end of tubular casing 2I fits into and is supported by a suitable adapter such, for example, as the tubular member 25 which, in turn, is secured to the terminal cap 4.

The tubular casing 2| is surrounded by a plurality of ceramic shell members 22 which are concentrically disposed with respect to the tubular casing 2|. Associated with each end of each of the shell sections 22 is a supporting metal annulus 26. These supporting members 26 are secured to the end iianges of the ceramic shell sections 22 by any suitable means such as by the bolts 21. The inner periphery of each annular member 26 beds upon a flexible or resilient ringlike member 28 mounted sungly about the casing 2 I. Thus, it will be seen that the weight of the ceramic shells 22 is supported by the casing 2I through the annular supporting members 26 and the resilient rings 28. Slight bending of the casing 2I due to the heavy weight of the ceramic shell sections 22 is accommodated since the brittle shell sections together form an articulated shell enclosing the casing 2I. In this way radial shocks due to vertical motion at either end caused by ground shock or reaction to motion of the vertical operating rod and other vertically moving parts as examples, are eiectively absorbed by the resilient rings 28 and hence are not transmitted to the shell sections 22.

For the purpose of preventing the transmission of shocks longitudinally through the ceramic shell sections 22, I provide a plurality of ring-like resilient members 29 which allow limited cushioned axial motion by one or any of the ceramic shells 22 with respect to an adjacent shell, or with respect to either end structure. Thus, a shock from a source outside the interrupter such, for example, as a ground tremor, reaction to oil flow and other causes will not be likely to cause breakage of the shells 22, and furthermore the overall length of the interrupter unit 5 can be increased to any desired value within the limits imposed by the ability of the casing 2I to withv stand bending stress.

The overall insulating properties of the interrupting unit 5 are improved if the space between the insulating tube 2| and the ceramic shells 22 is lled with a suitable dielectric such as oil, for example. In order to insure that this insulating oil will be evenly distributed throughout the length of the interrupting unit 5 at all times, I provide suitable communicating ports such as 30 disposed through the annular supporting members 26. At least one port such as 30 should be located at the top portion of the supporting members 26 to bleed air from the porcelain shells and at least one port 3B should be disposed at the bottom t0 facilitate oil drainage and to insure that the level of the insulating oil will be equalized through the length of the interrupter. Fluid is maintained within the space between casing 2| and the shells 22 from a suitable gravity reservoir such as 3| which communicates with the interrupter unit through the passageway 32. In order to seal adjacent surfaces of the annular supporting members 26, the metal Sylphon bellows 33 are brazed or welded between each adjacent pair to constitute a convenient manufacturing unit. The end bellows 34 forms a similar seal between the terminal cap 4 and the adjacent annular member 26 while the other end bellows 35 forms a seal between the wall of the housing 3 and the adjacent annular supporting member 26.

In view of the above description, it is clear that the whole shell comprises an articulated weather protecting cover member whose load is distributed uniformly along the back bone constituted by the interrupter casing and thatfby the invention, it is possible to increase the volt-5.",

age rating of interrupters and at the same time to provide an insulating structure ywhich is relatively free of the harmful eiects caused by Vibration and shocks from whatever cause.

It will be understood that my invention is not limited to the specific details of construction and arrangement thereof herein illustrated, and that changes and modifications may be made without departing from'the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Enclosing structure for a high voltage electrical device comprising a firmly supported horicasing member, an inwardly projecting metallic flange secured to each end of each shell section, a plurality of annular members of ilexible material disposed on said casing and operably related with the inner surfaces of said Vflanges to form an articulated shell around said casing thereby to accommodate bending of said casing and to prevent the transmission of shocks to said shells, yieldable bellows means interposed between opposed surfaces of adjacent iianges and to render said shell iluid tight, in said shell completely surrounding said casing, a first port disposed in a lower portion of each of said anges for aiding in equalizing the level of said liquid surrounding said casing, and a second port in each of said anges above the normal level of said liquid to prevent the accumulation of localized excessive pressures along the length of said shell thereby to facilitate the liquid level equalizing action of said rst ports.

2. Enclosing structure for a high voltage electrical device comprising a rmly supported horizontally disposed semi-rigid hollow casing member of insulating material, a plurality of ceramic shell sections disposed in spaced relation about said casing member, an inwardly projecting metallic flange secured to each end of each shell section, an annular member of flexible material interposed between said surfaces of each of said flanges, resilient means interposed between adjacent opposed Surfaces of some of said anges to against longitudinal movement, said shell sections forming an articulated shell around said casing thereby to accommodate bending of said casing, yieldable bellows means interposed between opposed surfaces of adjacent flanges and secured thereto to render said shell iiuid tight, liquid dielectric material in said shell completely surrounding said casing, and means including an opening in some of said anges for maintaining THELLWELL R. COGGESHALL.

REFERENCES CITED The following references are of record in the of this patent: 

